1. Field of the Invention
This invention relates generally to edge board connectors and more particularly to electrical connectors having locking means adapted to releasably secure printed circuit boards having electrical conducting strips disposed along one edge.
2. Description of the Prior Art
Electrical connectors for making connections to printed circuit boards are generally known in the art. An example of such an electrical connector is disclosed in U.S. Pat. No. 2,928,063 to Gammel.
These connectors, generally known in the art as edge connectors, are adapted to make electrical connections to a printed circuit board having a plurality of parallel conducting strips along one edge. Once the edge of the printed circuit board is inserted into the connector, spring contact terminals within the connector housing exert a force against the conductive strips on the printed circuit board to ensure a tight connection. However, such connections may become loose due to vibration and jarring causing interruption of the electrical circuit in which the connector is used.
Others have tried to solve this problem by various means. U.S. Pat. No. 4,416,496 to Brefka discloses an anchor for securing a printed circuit board to a connector. In this apparatus, two anchors are used, each fastened to an end of the connector by a screw. Each anchor contains a pin perpendicular to the printed circuit board, adapted to be inserted into a hole in the printed circuit board. However, this type of arrangement is only adaptable for making connections between two printed circuit boards in a side by side configuration. Moreover, due to the separate pieces, this type of arrangement would be expensive to manufacture and rather cumbersome to assemble.
Another method of securing a printed circuit board to a connector is disclosed in a French Pat. No. 2,562,338. In this connector assembly, a latch means is used to secure theth printed circuit board to the connector. The latch means is formed from a portion of the back wall of the housing by making two parallel slits in the back wall of the housing perpendicular to the axis of the housing, each slit extending the height of the housing. That portion disposed between the slits is then free to be pulled away from the housing. A tab is formed on the top portion of the latch means and is received into a slot on a printed circuit board. The printed circuit board is removed by pulling the latch means away from the back wall of the housing. However, in such a design the force required to release the latch results in a torque about the connector housing axis resulting in a considerable force in a direction parallel to the plane of the printed circuit board. Because of this force, such a latching means may not be suitable for applications where the connector is rigidly attached to another printed circuit board. In such applications this force may cause damage to the printed circuit board to which the connector is attached or to the connections between the housing and that board.